Yes, there is currently only one mandrin dive available. The "say" there are mandrin fish off of the house reef, but I did not personally see any. Also, you can only dive the house reef until 5 p.m. and after that you have to pay. They have the diving set up so that squeezing in 5 dives between 8:oo a.m. and 5 p.m. (when the house reef diving is free) is almost impossible, although I did it a few times. Your nitrogen uptake is much riskier, obviously. So to dive the mandrin dive for free, you have to skip the afternoon dive, or pay an additional $30 for the extra 4th dive. They say it's because of the currents, but I tend to lean to the cash flow side of the argument. I managed to spend an extra $30 every day for 15 days
, so I had $450 in diving extras by the end of the trip. There are liveaboards and other resorts competing for the mandrins. I got lucky oin the last dive because it was only me and another diver, and the fish were mating like crazy.
Nonetheless, you will have a fantastic time there. In the photo room, try to bring all of your tools, chargers, lenses, ports, CF cards, etc in the room and put them on the lower shelf. If you get a room at the other end of the resort like I did, making changes to your camera and housing is a hassle if you have to walk all the way to the room and back multiple times. It is also essential to bring Asian converters (the two prong kind) because the camera room only has a section of it wioth U.S. plugs, and that area is the first to be gobbled up by photographers. I has my own converters and thus my own little piece of paradise. Also keep in mind that you will be shooting more photographs than normal due to the wild animals and unusual animal behavior you will encounter. Consequently, your batteries get drained faster. I made what is perhaps the best night dive of my life and, go figure, my camera battery died just after I shot my first picture. I tended to juice my batteries every 2-3 dives depending on how many frames I shot.
When you get back from the boat dives be sure to consider a snorkel on the house reef. As I mentioned previously, there are juveniel batfish, but one day we found sargassam frogfish. Here are two shots of them at the surface. The house reef has hidden treasures 

Joe

